﻿/************************************************************************

   Extended Silverlight Toolkit

   Copyright (C) 2010-2012 Xceed Software Inc.

   This program is provided to you under the terms of the Microsoft Public
   License (Ms-PL) as published at http://extendedsilverlight.codeplex.com/license

   Please purchase a commercial version of this toolkit if you are using
   it in a commercial product. The commercial versions support the project,
   and also include more features for each control, priority support,
   source code, updates, removed watermark, and a proprietary license.

   Visit http://xceed.com and follow @datagrid on Twitter.

  **********************************************************************/

using System;

namespace Xceed.Silverlight.Data
{
  internal sealed class GroupCacheEnumerator : GroupCacheEnumeratorBase
  {
    #region Constructor

    internal GroupCacheEnumerator(
      IAsyncEnumerator<DataPath> childEnumerator,
      IContextualCompareHelper compareHelper,
      IContextualItemHelper itemHelper,
      IContextualGroupHelper groupHelper,
      IContextHelper contextHelper,
      int cacheSize )
      : base( childEnumerator, compareHelper, itemHelper, groupHelper, cacheSize )
    {
      if( contextHelper == null )
        throw new ArgumentNullException( "contextHelper" );

      m_contextHelper = contextHelper;
    }

    #endregion

    protected override DataSourceContext GetCurrentContext()
    {
      return m_contextHelper.GetContext();
    }

    #region Private Fields

    private readonly IContextHelper m_contextHelper;

    #endregion
  }
}
